The emergence of angiosperms in tropical forests at the expense of the gymnosperms, their ancestral relatives, was one of the most important events in the evolutionary history of terrestrial plants. Gymnosperms were nearly eliminated from the tropics after the evolution of angiosperms in the early Cretaceous, yet conifers of the Podocarpaceae are among the few gymnosperm families that persist in tropical forests worldwide. Podocarps are often considered to be restricted to montane sites in the tropics, a feature of their biogeography that is used by paleoecologists to reconstruct past forest communities. However, podocarps also occur in the lowland tropics, where they can be the dominant component of forest canopies. Podocarps have proved to be remarkably adaptable in many cases: members of the family have a semi-aquatic lifestyle, exhibit drought tolerance and resprouting, and include the only known parasitic gymnosperm. Other intriguing aspects of podocarp physiology include the mechanism of water transport in the leaves and the conspicuous root nodules, which are not involved in nitrogen fixation but instead house arbuscular mycorrhizal fungi. Perhaps most surprising, paleobotanical evidence indicates that far from being ‘relict’ members of tropical forest communities, podocarps have been dispersing into the tropics since the late Eocene epoch more than 30 million years ago. These and other aspects of the Podocarpaceae explored in this volume have far-reaching implications for understanding the ecology and evolution of tropical rain forests.

Inositol phosphates are a group of organic compounds found widely in the natural environment. They are important in agriculture because they constitute most of the phosphorus in grain seeds, but they cannot be digested by some animals. As a result, considerable research has been directed towards improving the digestibility of inositol phosphates in animal diets. Inositol phosphates are also abundant in soils and water bodies, yet a clear understanding of their behaviour in the environment remains elusive. This is surprising given the importance of phosphorus in the nutrition of both terrestrial and aquatic ecosystems. Written by leading experts, this book brings together critical reviews on inositol phosphates in agriculture, ecology, and the environment. The sixteen chapters cover a diverse range of topics, including the synthesis and hydrolysis of inositol phosphates, their role in animal nutrition, and their fate in soils and aquatic ecosystems. It will prove valuable to a wide readership in the agricultural and biological sciences, and will serve as a unique reference source on this emerging topic.

Organic Phosphorus in the Environment.

Organic Phosphorus

Edited by BL Turner, Smithsonian Tropical Research Institute, Panama; E Frossard, ETH Zurich, Switzerland; DS Baldwin, CSIRO Murray-Darling Freshwater Research Centre, Albury, Australia. Organic phosphorus is involved in almost every biological process. Organic forms of phosphorus often dominate in soils and aquatic systems and many organisms possess complex mechanisms enabling them to access phosphorus from organic compounds. However organic phosphorus remains the most poorly understood aspect of the global phosphorus cycle. This book brings together the latest research and opinion on the biogeochemistry of organic phosphorus from a wide range of disciplines and focuses specifically on the characterisation and transformations of organic phosphorus in terrestrial and aquatic systems. It examines analytical procedures for the chemical characterization of organic phosphorus in environmental samples, processes regulating organic phosphorus in the environment, and integration of the process at the ecosystem level. Ecological, chemical, microbiological and analytical aspects are explored. Written by a team of leading experts, the book will provide an invaluable reference for all those interested in organic phosphorus."